EP0184390A1 - Extrusions-, Förder- und Schneidesystem - Google Patents

Extrusions-, Förder- und Schneidesystem Download PDF

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Publication number
EP0184390A1
EP0184390A1 EP85308666A EP85308666A EP0184390A1 EP 0184390 A1 EP0184390 A1 EP 0184390A1 EP 85308666 A EP85308666 A EP 85308666A EP 85308666 A EP85308666 A EP 85308666A EP 0184390 A1 EP0184390 A1 EP 0184390A1
Authority
EP
European Patent Office
Prior art keywords
strand
cutter
propellant
time
cutting
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP85308666A
Other languages
English (en)
French (fr)
Other versions
EP0184390B1 (de
Inventor
Richard Austin Rollyson
Peter Daniels Wesson
Paul Samuel Zerwekh
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hercules LLC
Original Assignee
Hercules LLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hercules LLC filed Critical Hercules LLC
Publication of EP0184390A1 publication Critical patent/EP0184390A1/de
Application granted granted Critical
Publication of EP0184390B1 publication Critical patent/EP0184390B1/de
Expired legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C06—EXPLOSIVES; MATCHES
    • C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
    • C06B21/00—Apparatus or methods for working-up explosives, e.g. forming, cutting, drying
    • C06B21/0033—Shaping the mixture
    • C06B21/0075—Shaping the mixture by extrusion
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23D—PLANING; SLOTTING; SHEARING; BROACHING; SAWING; FILING; SCRAPING; LIKE OPERATIONS FOR WORKING METAL BY REMOVING MATERIAL, NOT OTHERWISE PROVIDED FOR
    • B23D36/00—Control arrangements specially adapted for machines for shearing or similar cutting, or for sawing, stock which the latter is travelling otherwise than in the direction of the cut
    • B23D36/0008—Control arrangements specially adapted for machines for shearing or similar cutting, or for sawing, stock which the latter is travelling otherwise than in the direction of the cut for machines with only one cutting, sawing, or shearing devices
    • B23D36/0033—Control arrangements specially adapted for machines for shearing or similar cutting, or for sawing, stock which the latter is travelling otherwise than in the direction of the cut for machines with only one cutting, sawing, or shearing devices for obtaining pieces of a predetermined length
    • B23D36/0058—Control arrangements specially adapted for machines for shearing or similar cutting, or for sawing, stock which the latter is travelling otherwise than in the direction of the cut for machines with only one cutting, sawing, or shearing devices for obtaining pieces of a predetermined length the tool stopping for a considerable time after each cutting operation
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T83/00—Cutting
    • Y10T83/465—Cutting motion of tool has component in direction of moving work
    • Y10T83/4653—With means to initiate intermittent tool action
    • Y10T83/4656—Tool moved in response to work-sensing means
    • Y10T83/4664—With photo-electric work-sensing means
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T83/00—Cutting
    • Y10T83/525—Operation controlled by detector means responsive to work
    • Y10T83/533—With photo-electric work-sensing means
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T83/00—Cutting
    • Y10T83/525—Operation controlled by detector means responsive to work
    • Y10T83/54—Actuation of tool controlled by work-driven means to measure work length

Definitions

  • This invention relates to methods for continuously extruding, conveying and cutting strands of solid propellants to produce so-called "stick” propellants in precise lengths.
  • DC motor cutters can overcome the tendency for extreme stick length variability, but cannot provide a standard deviation of, for instance, from 0.05 cm to 0.6 cm, which may be required to meet length tolerance limits for a mean stick length of about 356 mm commonly accepted in the industry. Variations in the extrusion rate are responsible for unacceptable variations in length, even when the best available cutter and controlling microprocessor and software are used. Known methods for utilizing feedback to control the extrusion velocity are not practical for high velocity propellant extrusion.
  • a method for continuously conveying and cutting an extruded strand of a solid propellant to produce sticks of a desired length that is substantially independent of variations in strand velocity in which the extruded strand is continuously conveyed past a microprocessor -controlled cutter, that cuts the strand after it receives an electronic signal, and the cut sticks are collected by a collector downstream from the cutter, the transmission time of the signal and the mechanical response time of the cutter constituting an inherent cutter delay time, is characterized in that the arrival of the forward end of the strand at a first sensing point that is between the cutter and the collector activates the microprocessor to begin to count and store a first number of equally spaced time pulses; the arrival of the forward end of the strand at a second sensing point that is between the first sensing point and the collector, and is spaced from the first sensing point by a distance that is greater than the distance the strand travels during the cutter delay time, activates the microprocessor to begin to count and store a second number of equally spaced
  • the method according to the invention can be summarized as a system that uses sensors to measure the speed of movement of a strand over a fixed increment to a fixed distance from a cutter that approximates the desired length of the cut part, and uses that measurement to determine the point beyond that fixed distance at which the strand must be cut to make its length independant of its speed of movement, thus producing cut sticks of constant length.
  • the propellant extrusion rate may range,for example, between about 120 and 360 mm per second.
  • Figures 1 and 1A are simplified views in perspective of apparatus 10 used in practice of this invention.
  • Figure 1 shows extruder 12 extruding propellant strand 14 that is pneumatically conveyed by introduction of air into inlet 16.
  • Figure 1A is an expanded view of cutter 18, conveyor 28 and plenum chamber 29.
  • Figure 2 is a schematic of propellant strand 14, cutter 18 and sensors P O and P 1 .
  • Figure 3 graphically depicts in two interrelated graphs the relationship between propellant strand positions P O ,P 1 and P 2 and time.
  • Figure 4 is a bar graph depicting the precision obtained in a practice of this invention.
  • extruder 12 has a ram in housing 22 that extrudes a propellant strand 14 from previously prepared pieces in the form of so-called "carpet rolls", such as shown at 23,24 as they are being fed into inlet 26 for extrusion.
  • the propellant strand 14 exits a die orifice (not shown) at the end of extruder 12, travels through a short tube and then onto the pneumatic conveyor 28 between guides 30,32.
  • a suitable pneumatic conveyor is available from Jetstream Systems Company under the designation JETSTREAM R .
  • Air forced through inlet 16 into plenum chamber 29 of the conveyor provides a fluid carrier as the air exits orifices 36 (see Figure 1A), which are dispersed along the length of the conveyor to lift the propellant strand 14 as it moves to cutter 18.
  • the pressure of air in chamber 29 is about 5 inches of water above atmosphere.
  • the existing jets of air cool the propellant strand 14.
  • a DC (direct current) servo motor cutter 18 is designed to cut through the propellant strand 14 when the motor is activated by a signal from a MM-10 microprocessor, available from Industrial Indexing Systems Company.
  • the motor for the cutter 18 is available from Inland Motors Company as model TTR-2042-3010, with amplifier SM6015-22 to amplify the signal.
  • a blade 38 is mounted on the shaft of the motor, and the MM-10 microprocessor is programmed to drive the motor through a single rotation of the shaft that provides the cutting action, with prescribed acceleration and maximum velocity and deceleration rates.
  • the transmission time of the signal to activate the motor and the mechanical response time of the cutter produce an inherent cutter delay time between the initiation of the signal and the completion of the cutting action.
  • the sensing elements at P 0 and P 1 are carried by sensor housing and support 40 ( Figure 1) and utilize non-contacting optical sensors, so that the propellant strand is detected without the possibility of product deformation or dangerous heat generation.
  • the sensor locations P 0 and P 1 may be about 1.25-2.0 cm apart along the conveyor.
  • the output of sensors at P O ,P l is used to actuate a binary codes decimal (BCD) counter 46, connnected to a precision oscillator 50 and digital circuitry 46,48.
  • BCD binary codes decimal
  • the counter 46 is initialized in its "load” mode, at an output value, preset by the binary rotary switches 48, that corresponds to the inherent cutter delay (which may be,for example, about 55 milliseconds).
  • the load input is deactivated and the counter begins to count pulses from the precision oscillator 50. It counts down from the present value, becoming more negative in value until the propellant reaches P 1 . At this point the count direction is reversed and the counter output value begins to increase toward zero. The counter output value will reach zero when the second count equals the difference between the first count and the number of time pulses that is equivalent to the present output value corresponding to the inherent cutter delay.
  • propellant sticks can be pneumatically conveyed after cutting and deposited in a bin 42.
  • th:s transportor is the same pneumatic conveyor as used in pneumatic conveyance of strand 14 prior to cutting.
  • the plenum chamber 29 extends the lengrh cf device 10.
  • Figure 4 shows the results of utilizing a propellant stick manufacturing procedure such as described above.
  • the 80 sticks in Figure 4 are nominally 14" sticks with a standard deviation of between 0.020 and 0.0230 inches and a mean length of 13.969 inches.
  • the stick has a diameter of about 0.248 inches and comprises by weight about 62.5% nitrocellulose, 36.7% diethyleneglycoldinitrate, 0.45% Akardite II, 0.25% Ethyl Centralite and 0.10% of graphite and magnesium oxide.
  • the automated stick propellant manufacturing apparatus of Figure 1 as described above may be arranged so that the die has many orifices through which a plurality of strands are extruded and laid in individual trays of a multiple track pneumatic conveyor. Each track preferably has a separate cutter and optical sensor combination.
  • the method of this invention is suitable for use in manufacture of stick propellant from solvent-type single, double and triple base propellants as well as solvent-less- type double and triple base propellants, from horizontal as well as vertical presses.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Extrusion Moulding Of Plastics Or The Like (AREA)
  • Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
  • Refuse Collection And Transfer (AREA)
  • Accessories And Tools For Shearing Machines (AREA)
EP85308666A 1984-11-28 1985-11-28 Extrusions-, Förder- und Schneidesystem Expired EP0184390B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US06/675,504 US4585600A (en) 1984-11-28 1984-11-28 Extrusion, conveyance, and cutting system
US675504 1996-06-28

Publications (2)

Publication Number Publication Date
EP0184390A1 true EP0184390A1 (de) 1986-06-11
EP0184390B1 EP0184390B1 (de) 1989-01-25

Family

ID=24710796

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85308666A Expired EP0184390B1 (de) 1984-11-28 1985-11-28 Extrusions-, Förder- und Schneidesystem

Country Status (6)

Country Link
US (1) US4585600A (de)
EP (1) EP0184390B1 (de)
JP (1) JPS61192494A (de)
CA (1) CA1247050A (de)
DE (1) DE3567853D1 (de)
NO (1) NO167500C (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3622011C1 (en) * 1986-07-01 1987-12-10 Dynamit Nobel Ag Process for cutting off defined lengths from strands of propellant charge powders

Families Citing this family (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4767577A (en) * 1985-10-03 1988-08-30 Mueller Dietmar Process and apparatus for producing plastic-bound propellant powders and explosives
GB8527661D0 (en) * 1985-11-08 1985-12-11 Ici Plc Catalyst supports & precursors
DE3805317A1 (de) * 1988-02-20 1989-08-24 Fraunhofer Ges Forschung Verfahren und vorrichtung zur herstellung von treibladungsgranulat
DE3821311A1 (de) * 1988-06-24 1989-12-28 Werner & Pfleiderer Verfahren und vorrichtung zur sicherung des mischvorganges bei der herstellung strangfoermiger explosivstoffe und treibmittel in einem schneckenextruder
US5129304A (en) * 1988-08-29 1992-07-14 Apv Chemical Machinery Inc. Method and apparatus for processing potentially explosive and sensitive materials for forming longitudinally perforated extrudate strands
US4945807A (en) * 1988-08-29 1990-08-07 Apv Chemical Machinery, Inc. Method and apparatus for processing potentially explosive and sensitive materials for forming longitudinally perforated extrudate strands
US5103684A (en) * 1990-05-30 1992-04-14 The United States Of America As Represented By The Secretary Of The Air Force Material cutting tool
US5149478A (en) * 1991-11-18 1992-09-22 The Standard Products Company Forming decorative trim strips from continuous extrusions
US5391025A (en) * 1992-04-21 1995-02-21 Thiokol Corporation Propellant grain machining device
EP0616879B2 (de) * 1992-10-29 2000-04-26 Barwell International Limited Eine hydraulischbetätigte Kolben-Strangpresse
US5419501A (en) * 1993-11-15 1995-05-30 Thiokol Corporation Propellant grain cutting assembly
US5487851A (en) * 1993-12-20 1996-01-30 Thiokol Corporation Composite gun propellant processing technique
US5501132A (en) * 1994-08-31 1996-03-26 Global Environmental Solutions, Inc. Dry preparation of particulate solid energetic material
FR2728562B1 (fr) * 1994-12-22 1997-01-24 Poudres & Explosifs Ste Nale Procede de fabrication en continu de chargements pyrotechniques a liant silicone et compositions susceptibles d'etre mises en oeuvre par ce procede
US5619073A (en) * 1995-08-15 1997-04-08 Propellex Corporation Propellant grains and process for the production thereof
US5670098A (en) * 1996-08-20 1997-09-23 Thiokol Corporation Black powder processing on twin-screw extruder
US5872715A (en) * 1997-07-16 1999-02-16 Bechtle; Samuel J. Automatic inspection and certification system
US6112132A (en) * 1998-03-06 2000-08-29 Ultra Clean Technology Systems & Service, Inc. Automated tube cutting apparatus and method
US6708591B1 (en) 1999-05-03 2004-03-23 Rockford Manufacturing Group, Inc. Clutchless wire cutting apparatus
US6315930B1 (en) 1999-09-24 2001-11-13 Autoliv Asp, Inc. Method for making a propellant having a relatively low burn rate exponent and high gas yield for use in a vehicle inflator
US6458302B1 (en) 2000-03-23 2002-10-01 Tekni-Plex, Inc. System and method for forming plastic articles
US6863855B2 (en) 2001-05-15 2005-03-08 Avery Dennison Corporation Method of making a cable tie using insert molding
US20040107809A1 (en) * 2002-12-04 2004-06-10 Borzym John J. Automatic feed system for tube shear device and position registration system for same
US11578014B1 (en) * 2019-12-30 2023-02-14 The United States Of America As Represented By The Secretary Of The Army Process for preparing pyrophoric foam granules

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE803269C (de) * 1948-10-02 1951-04-02 Clemens Fa Ludwig Querschneider fuer fortlaufend bewegte Bahnen aus Papier, Pappe o. dgl.
DE1561709A1 (de) * 1966-10-05 1970-07-23 Boewe Boehler & Weber Kg Masch Schneidautomat
DE1779538A1 (de) * 1967-08-24 1971-09-23 Schiesser Ag Rubber & Railroad Automatische Maschine zum massgenauen Ablaengen von stranggepressten Straengen und Schlaeuchen
US3969054A (en) * 1975-07-11 1976-07-13 The United States Of America As Represented By The Secretary Of The Army Length sensing single strand shuttle cutter apparatus for cutting propellant grain

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3114282A (en) * 1958-04-05 1963-12-17 Reifenhauser K G Apparatus for the transverse severance of continuously moving tubular structures
US4016790A (en) * 1963-10-01 1977-04-12 Zellweger, Ltd. Regulation of electronically operated quality control equipment
GB1107878A (en) * 1964-05-29 1968-03-27 Demag Ag Cropping and dividing cutters for wire and light-section steel
US3717058A (en) * 1970-06-02 1973-02-20 Eagle Mfg Corp Flying cut-off press
US3712165A (en) * 1970-08-17 1973-01-23 Anetsberger Bros Inc Pastry product production system
FR2264642A1 (en) * 1974-03-21 1975-10-17 Herstal Sa Automatic cutting of extruding tubing for making cartridge cases - to produce consistently cut lengths regardless of the extrusion rate
SE7404839L (sv) * 1974-04-10 1975-10-13 Nitro Nobel Ab Anleggning for kontinuerlig framstellning av sprengemne innehallande sprengolja
DE3041705A1 (de) * 1980-11-05 1982-06-09 Horst 5653 Leichlingen Pickhardt Trennvorrichtung zum abtrennen abgezogenen extrudierten strangfoermigen gutes in gleich lange abschnitte
GB2107638B (en) * 1981-10-22 1985-11-13 Secr Defence Cutting apparatus for extruded materials

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE803269C (de) * 1948-10-02 1951-04-02 Clemens Fa Ludwig Querschneider fuer fortlaufend bewegte Bahnen aus Papier, Pappe o. dgl.
DE1561709A1 (de) * 1966-10-05 1970-07-23 Boewe Boehler & Weber Kg Masch Schneidautomat
DE1779538A1 (de) * 1967-08-24 1971-09-23 Schiesser Ag Rubber & Railroad Automatische Maschine zum massgenauen Ablaengen von stranggepressten Straengen und Schlaeuchen
US3969054A (en) * 1975-07-11 1976-07-13 The United States Of America As Represented By The Secretary Of The Army Length sensing single strand shuttle cutter apparatus for cutting propellant grain

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3622011C1 (en) * 1986-07-01 1987-12-10 Dynamit Nobel Ag Process for cutting off defined lengths from strands of propellant charge powders

Also Published As

Publication number Publication date
DE3567853D1 (en) 1989-03-02
NO167500B (no) 1991-08-05
EP0184390B1 (de) 1989-01-25
NO854752L (no) 1986-05-29
CA1247050A (en) 1988-12-20
JPS61192494A (ja) 1986-08-27
NO167500C (no) 1991-11-13
US4585600A (en) 1986-04-29

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